How Do Solar Panels Work?

Thinking about installing solar panels but want to understand exactly what you’re investing in? Here’s what you need to know about how solar panels work and what that means for your home.

The basic process: Turning sunlight into electricity

Solar panels generate electricity through photovoltaic (PV ) cells: the individual squares you see on each panel. These cells are made from multiple layers of a semi-conducting material (i.e. a material whose electrical conductivity can be controlled) – usually silicon. Sunlight shining on the cell allows a current to flow across the layers, producing electricity. The stronger the sunshine, the more electricity is produced. But solar panels don’t need direct sunlight to work; they can still produce significant amounts of energy on cloudy or overcast days. 

Electricity produced by solar panels is converted into power for your home using an inverter. The inverter converts the direct current (DC) generated by the panels to alternating current (AC), which is what your domestic appliances use. No fuel, no moving parts, no noise.

Here’s a simple version of what happens:

  1. Daylight hits the solar cells. Note: it’s daylight that matters, not direct sunshine. Even on cloudy days, your panels generate electricity
  2. The cells create a direct current (DC). This happens almost instantly as photons from sunlight energise electrons in the silicon material
  3. An inverter converts DC to AC electricity. Your home appliances run on alternating current (AC), so this conversion is essential
  4. You use the electricity. During daylight hours, you’re powering your home with free solar energy
  5. Excess energy is exported. Any electricity you don’t use can be sent to the National Grid and earn you money

The entire process happens in seconds, and your panels will do this reliably for 25-30 years or more.

The key components of your solar system

Understanding the main parts of your system helps you appreciate what you’re investing in:

  • Solar panels sit on your roof – or in your garden or on land you can spare – and do the work of capturing daylight. Modern panels are typically monocrystalline; these are the most efficient type, converting around 15-22% of sunlight into electricity. That efficiency means you need less space to generate the power you need
  • The inverter is your system’s power converter. It transforms the DC electricity from your panels into the AC electricity your home uses. This is a crucial component – without it, your solar-generated power would be useless for running household appliances
  • Your monitoring system tracks exactly how much electricity your panels are generating, how much you’re using, and how much you’re exporting. Most systems come with an app that lets you watch your generation in real-time.

Types of solar panels

There are three main types of solar panel:

  • Monocrystalline: The oldest and most developed of the three technologies. As the name suggests, monocrystalline panels are created from a single continuous crystal structure. A monocrystalline panel can be identified from the solar cells which all appear as a single flat colour, usually black
  • Polycrystalline: Made from similar silicon material to monocrystalline panels but instead of going through the slow and more expensive process of creating a single crystal, molten silicon is just put into a cast and cooled with a seed crystal. These are the most common panels used today and tend to have a bluish colour. They convert 15-20% of sunlight into electricity
  • Thin film: Thin film panels are made of very thin non-crystalline layers of PV materials (up to 300 times thinner than mono- or polycrystalline PVs, in fact). This means thin film panels can be shaped to curved surfaces or surfaces where it wouldn’t work to have a rigid panel. Thin film panels tend to be slightly less efficient than the other types of panels, however – 10-20%.

Solar panel performance in the real world

Here in Sussex, we’re lucky to be in one of the sunnier regions of the UK. But what does that actually mean for solar panel performance?

Your panels generate the most electricity during summer months when days are longer and the sun is higher in the sky. However, they continue working throughout winter, just at reduced output due to shorter days rather than cold weather. In fact, cold temperatures actually improve panel efficiency, because the electrons can move more freely within the solar cells.

And on cloudy, overcast days, your panels still work. They may generate 10-25% of their peak output on overcast days, but they’re still producing energy you can use in your home. As we like to remind you: it’s daylight that counts, not direct sunshine.

So, for a typical Sussex home with a 12-panel system, you might generate around 3,500-4,500 kWh per year – though of course this will depend on your roof’s orientation, pitch, and any shading.

Without battery storage, you will likely use around 33% of that 3,500-4,500kW, and the rest will go to the grid. However, if you add battery storage, you’ll unlock the remaining 67% of what your system generates.

Getting paid for your solar energy

Under the Smart Export Guarantee (SEG), you’re paid for every unit of electricity you export back to the grid. Rates vary by supplier, with some time-of-use tariffs paying higher rates during peak hours.

This matters because you won’t use all the electricity you generate. On sunny days, especially during summer, your panels often produce more power than your home needs. That excess electricity flows back to the grid, and you receive payment for it.

Maximising your solar investment

To get the most value from your solar panels, consider adding battery storage. A solar battery captures your excess daytime generation and stores it for evening use, when electricity is typically most expensive and your panels aren’t producing. This is particularly valuable during winter, when your peak electricity use happens after dark.

But even if you choose not to add battery storage, there are still ways you can maximise the value you get from your solar panels. Shift your electricity use to daylight hours when possible. Run your washing machine, dishwasher, and other high-energy appliances during the day to use your free solar electricity instead of buying power from the grid.

What about installation?

Professional installation is essential to get the most from your solar system. A credible installer should assess your roof’s structural capacity, calculate optimal panel placement to avoid shading, and design a mounting system that distributes weight properly across your roof. Here at Sopoco, we carry out detailed structural calculations and shade reports before every installation. We also design our mounting systems to stagger the weight distribution, protecting your roof structure for the long term.

The installation itself typically takes 1-2 days, depending on system size. Once complete, your system connects to the grid, allowing you to both use and export electricity seamlessly.

Solar panels work by converting daylight into electricity you can use immediately or export for payment. The technology is proven, reliable, and requires minimal maintenance once installed.

With current energy prices, a typical solar installation can pay for itself within 8-12 years through electricity bill savings and export payments. Factor in the system’s 25-30+ year lifespan, and you’re looking at savings of tens of thousands of pounds.

And right now, there’s additional support available through the government’s Warm Homes Plan, and solar panels remain zero-rated for VAT until 2027, making this an excellent time to invest.

Contact:

  • 35 Offington Gardens, Worthing, West Sussex,
    BN14 9AU
  • sales@sopoco.co.uk
  • 01903 410980

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